理解Socket

服务器端代码：
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.net.ServerSocket;
import java.net.Socket;

public class Server {

public static void main(String[] args) {
ServerSocket ss = null;
Socket socket = null;
BufferedReader br = null;
try {
ss = new ServerSocket(6000);
while(true) {
socket = ss.accept();
br = new BufferedReader(new InputStreamReader(socket.getInputStream()));
String clientName = br.readLine();
System.out.println("Server Message: Hello, " + clientName + ", welcome you to the website.");
}
} catch (IOException e) {
e.printStackTrace();
} finally {
if (ss != null) {
try {
ss.close();
} catch (IOException e) {
e.printStackTrace();
}
}
if (socket != null) {
try {
socket.close();
} catch (IOException e) {
e.printStackTrace();
}
}
if (br != null) {
try {
br.close();
} catch (IOException e) {
e.printStackTrace();
}
}
}
}

}

客户端代码：
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.PrintWriter;
import java.net.Socket;
import java.net.UnknownHostException;

public class Client {

public static void main(String[] args) {
Socket socket = null;
BufferedReader br = null;
PrintWriter out = null;
try {
socket = new Socket("localhost", 6000);
br = new BufferedReader(new InputStreamReader(System.in));
//第二个参数为true,表示保留之前的值
out = new PrintWriter(socket.getOutputStream(), true);
System.out.println("请输入你名字:");
out.write(br.readLine());
out.flush();
} catch (UnknownHostException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
} finally {
if (socket != null) {
try {
socket.close();
} catch (IOException e) {
e.printStackTrace();
}
}
if (br != null) {
try {
br.close();
} catch (IOException e) {
e.printStackTrace();
}
}
if (out != null) {
out.close();
}
}
}

}